Exciting news: seems that open-source FPGA tools now support Lattice's (larger) ECP5 FPGAs well enough that David Shah reports bringing up a Linux on the open source CPU mor1k (Open RISC 1000 architecture).

Documenting the Lattice ECP5 bit-stream format. Contribute to SymbiFlow/prjtrellis development by creating an account on GitHub.

Project Trellis enables a fully open-source flow for ECP5 FPGAs using Yosys for Verilog synthesis and nextpnr for place and route. Project Trellis itself provides the device database and tools for bitstream creation.

Just so you are all aware, I am working with David Shah on the next gen myStorm boards project 'BlackEdge', Some of you may already have picked up features from our conversations on the mystorm irc channel.